Advances in the treatment of HIV disease have produced dramatic reductions in AIDS-related morbidity and mortality in the United States and Europe. However, despite lower drug prices and an increased focus on the global HIV epidemic, severe resource constraints in Africa, Asia and less developed countries throughout the world have limited the availability of antiretroviral therapy and opportunistic infection prophylaxis. With a distinguished track record of analysis and policy impact in the United States and Europe, we propose to build on over 10 years of experience examining the clinical impact, cost and cost-effectiveness of alternative HIV care strategies and expand efforts to three less developed countries. We propose the following aims: [unreadable] 1. To develop the Global AIDS Policy Model, a comprehensive and flexible state-transition model of the natural history and treatment of HIV disease in less developed countries. [unreadable] 2. To analyze data on HIV natural history, treatment efficacy, costs, and quality of life in each of 3 countries: Cote d'Ivoire, India, and South Africa. [unreadable] 3. To assess the clinical impact, cost, and cost-effectiveness of different strategies for antiretroviral therapy, opportunistic infection prophylaxis, and tuberculosis preventive therapy. In accordance with key areas of NIAID interest, these aims will help to develop practical and affordable methods for HIV treatment and inform the rational use of therapy in resource-diverse settings. The products of this proposal will investigate pressing HIV clinical and policy questions in each of these countries, and results will be provided to clinicians delivering care and to health officials responsible for shaping policy. Having already influenced HIV policy in the US through model-based cost-effectiveness analysis, the Global AIDS Policy Model team will formally address resource limitations for HIV care in these representative less developed countries. This project will elucidate questions of optimal HIV management for clinicians, public health officials, and policy makers, and it will provide a durable tool with which to address crucial questions in these countries and in other settings worldwide. [unreadable] [unreadable] [unreadable]